When a user equipment (UE) conducts a Third Generation Partnership Project (3GPP) inter-radio access technology (RAT) handover, it does not know the target RAT network capability until it complete the power save (PS) handover procedure. If the target RAT, such as Global System for Mobile Communications (GSM) enhanced data rates for GSM evolution (EDGE) radio access network (GERAN), cannot support certain internet protocol (IP) capability, the UE has to start WLAN or WiFi and then move the IP flow to WiFi, which takes a longer time and detrimentally impacts the user's experience. There is no mechanism for the UE to obtain 3GPP RAT network capability information before actual inter-RAT handover occurs.
In current access network discovery and selection function (ANDSF) policy, the validity conditions that indicate the conditions under which the policy should be applied are limited, such as only time and location. The condition is not associated with the services.
For the current ANDSF mechanism, the policy is applied before the UE makes the selection. There is no mechanism for the UE to reselect another network after the selection is made in case the selected network is not suitable after connection. For example, if a policy is that long term evolution (LTE) is always preferred over WiFi, but LTE 1, to which the UE is connected, is overloaded at this time, so WiFi needs to be considered as preferred over LTE.